SM U-106

History
German Empire
Name:	U-106
Ordered:	5 May 1916
Builder:	Germaniawerft, Kiel
Yard number:	275
Launched:	12 June 1917
Commissioned:	28 July 1917
Fate:	Sunk by mines 7 October 1917
General characteristics [1]
Class and type:	German Type U 93 submarine
Displacement:	798 t (785 long tons) surfaced 1,000 t (980 long tons) submerged
Length:	71.55 m (234 ft 9 in) (o/a) 56.05 m (183 ft 11 in) (pressure hull)
Beam:	6.30 m (20 ft 8 in) (o/a) 4.15 m (13 ft 7 in) (pressure hull)
Height:	8.25 m (27 ft 1 in)
Draught:	3.90 m (12 ft 10 in)
Installed power:	2 × 2,400 PS (1,765 kW; 2,367 shp) surfaced 2 × 1,200 PS (883 kW; 1,184 shp) submerged
Propulsion:	2 shafts, 2 × 1.70 m (5 ft 7 in) propellers
Speed:	16.4 knots (30.4 km/h; 18.9 mph) surfaced 8.4 knots (15.6 km/h; 9.7 mph) submerged
Range:	9,280 nmi (17,190 km; 10,680 mi) at 8 knots (15 km/h; 9.2 mph) surfaced 50 nmi (93 km; 58 mi) at 5 knots (9.3 km/h; 5.8 mph) submerged
Test depth:	50 m (164 ft 1 in)
Complement:	4 officers, 32 enlisted
Armament:	6 × 50 cm (19.7 in) torpedo tubes (four bow, two stern) 12-16 torpedoes 1 × 10.5 cm (4.1 in) deck gun 1 × 8.8 cm (3.5 in) deck gun
Service record
Part of:	Imperial German Navy: IV Flotilla 28 July 1917 – October 1917
Commanders:	Kptlt. Hans Hufnagel[2] 28 July 1917 – October 1917
Operations:	1 patrol
Victories:	1 merchant ships damaged (5,867 GRT) 1 warship sunk (957 tons)

SM U-106 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-106 was commissioned on 28 July 1917, under the command of Kapitänleutnant Hans Hufnagel, and participated in one wartime patrol starting on 2 September 1917. On 18 September 1917, during the First Battle of the Atlantic, U-106 was credited with the sinking of HMS Contest, an Acasta class destroyer, and damaging "City of Lincoln", a 5,867 ton steamer, in the Western Approaches.^[3] She was lost off Terschelling after striking a mine on 7 October 1917.^[4]

Design

German Type U 93 submarines were preceded by the shorter Type U 87 submarines. U-106 had a displacement of 798 tonnes (785 long tons) when at the surface and 1,000 tonnes (980 long tons) while submerged.^[1] It had a total length of 234 ft 9 in (71.55 m), a pressure hull length of 183 ft 11 in (56.06 m), a beam of 20 ft 8 in (6.30 m), a height of 27 ft 1 in (8.26 m), and a draught of 12 ft 10 in (3.91 m). The submarine was powered by two 2,400 metric horsepower (1,800 kW; 2,400 shp) engines for use while surfaced, and two 1,200 metric horsepower (880 kW; 1,200 shp) engines for use while submerged. It had two propeller shafts and two 1.7 m (5 ft 7 in) propellers. It was capable of operating at depths of up to 50 metres (160 ft).^[1]

The submarine had a maximum surface speed of 16.4 knots (30.4 km/h; 18.9 mph) and a maximum submerged speed of 8.4 knots (15.6 km/h; 9.7 mph).^[1] When submerged, it could operate for 50 nautical miles (93 km; 58 mi) at 5 knots (9.3 km/h; 5.8 mph); when surfaced, it could travel 9,280 nautical miles (17,190 km; 10,680 mi) at 8 knots (15 km/h; 9.2 mph). U-106 was fitted with six 50 centimetres (20 in) torpedo tubes (four at the bow and two at the stern), twelve to sixteen torpedoes, one 10.5 centimetres (4.1 in) deck machine gun, and one 8.8 centimetres (3.5 in) deck machine gun. It had a complement of thirty-six (thirty-two crew members and four officers).^[1]

Wreck

In 2009 the Royal Netherlands Navy found the wreckage of the ship north of Terschelling, while charting sea-routes. The news was made public in March 2011, after the ship's identity had been confirmed by German authorities and the crewmembers' families had been informed. The ship will stay in place as a wargrave.^[5][6]

Summary of raiding history

Date	Name	Nationality	Tonnage[Note 1]	Fate[7]
18 September 1917	HMS Contest	Royal Navy	957	Sunk
18 September 1917	City of Lincoln	United Kingdom	5,867	Damaged

References

Notes

1. Merchant ship tonnages are in gross register tons. Military vessels are listed by tons displacement.

Citations

1. Gröner 1991, pp. 12-14.
2. Helgason, Guðmundur. "WWI U-boat commanders: Hans Hufnagel". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 26 January 2015.
3. "British Destroyers". Retrieved 16 March 2011.
4. Helgason, Guðmundur. "WWI U-boats: U 106". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 25 January 2010.
5. "Marine vindt Duitse U-boot uit WO-I" (in Dutch). Retrieved 16 March 2011.
6. "Dutch navy finds sunken German submarine". Retrieved 16 March 2011.
7. Helgason, Guðmundur. "Ships hit by U 106". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 26 January 2015.

Bibliography

• Gröner, Erich; Jung, Dieter; Maass, Martin (1991). U-boats and Mine Warfare Vessels. German Warships 1815–1945. 2. Translated by Thomas, Keith; Magowan, Rachel. London: Conway Maritime Press. ISBN 0-85177-593-4.